zxr 750h1 front end.

[conordylan1]

hi everybody, i'm just about to do the same zxr rear wheel upgrade that travis did and was just wondering has anyone played around with the zxr 750 h1 front end ?  I have a donor bike with a blown engine and was told that the front end on these bikes was pretty amazing.  any advice would be really appreciated. 

[axiom-r]

I am not an expert but I have modded my bike to receive a Yamaha R1 front end.  I believe that most of the front end swaps (any of them) involve pressing the FJ stem out of the lower triple clamp and adapting it to work with the lower triple of the front end you are going to use.  The press fit has been described as a .0025 clearance press fit.

ALL BALLS ball bearing company makes "conversion sets" and it is possible (but unlikely) that you could find the proper bearing and not have to swap the stems.

On the top, typically, there is a spacer needed for the top triple clamp to seat properly and make the whole assembly fit the FJ neck. 

50 mm USD forks will fit into the FJ fame loop around the neck.  The steering stops are a individual mod problem as they are all slightly different. Some have to be ground down others have to be built up (extra material welded on).  Typically the USD forks are too short for the FJ as well so you may need to figure out extenders.

Bottom line is it can be done you just have to get the parts and start finding your path through the process.  There is some machining involved so if you cannot do this work yourself look for a local provider and start discussing the job with them.

tim

[RichBaker]

This site says they're 43mm tubes, same as a FZ1....You can bore the FJ triple so they'll fit...... Same as Frank did for the FZ1 tubes he put on Brutus. The 17" wheel is a good one, too... Go for it!

Front Suspension
43mm Telescopic forks.  adjustable preload and 12-way rebound damping, 120mm wheel travel.

Front Brakes
2x 310mm discs 4 piston calipers

Front Tyre
120/70 ZR17

[andyb]

This site says they're 43mm tubes, same as a FZ1....You can bore the FJ triple so they'll fit......

That site is occasionally wrong, incidentally.  Not in this case, as described by this site which confirms things.

Why though?  It's not a huge upgrade imo, as the "good" front end from the ZX7 didn't happen until the J/K models (91) when they gained USD forks (or the 94-97 ZX9R, which was the same, albeit with different braking options).  If you're gaining a 17" wheel, then it makes perfect sense, though.  You will also be losing some wheel travel, more than an inch (30mm) if what I'm reading is correct.  I believe the brakes are smaller, at 275mm vs the early FJ's 282mm or the later FJ's (89+) 290mm discs.  Unless youv'e got them in hand already and the price was right, I'd suggest going for a later FJ's front end, involving no changes at the triples at all, and you'd only need the sliders and down (and a set of monobloc brakes, y`know, while you're in there....)  The only issue with the later FJ front end is the narrow size of the 17" wheel, at 3.0" vs a more typical 3.5".

[andyb]

Sigh.  It's come to my attention that the later FJ brakes are 298mm.

So, want a real good laugh?  I used the same site that I specifically said wasn't reliable, for my numbers.


They list the 93 as 290mm.
They list the 91-92 ABS as 300mm.
They list 88-90 as 282mm.

So i just averaged things out.    Honest.  And anyhow, ARNIE, those are all bigger than the ZX7 brakes.  Though what size those are, I now start to wonder!   

[axiom-r]

I didn't even think to ask the year!  Just assumed... my bad.

Sounds much easier to deal with!

You can bore the FJ triple so they'll fit......

[conordylan1]

sorry should have said, its an 89 3cv with pitted fork tubes and the weakest springs on the planet. measured the zxr discs and turns out they are 310mm, chicken dinner or what. the plan is to fit the complete front end as the top yoke (triple clamp) has already been fitted with risers and renthal bars, (im only 5' 3" and the original set up is a bit of a stretch). So if the headstock stem can be made to fit the fj i should be onto a winner.  did a bit of looking and the zxr had been fitted with progressive springs and by my reckoning they have to be better than the stock yam items. So wider wheel, stronger springs, bigger brakes, stronger fork tubes and ready made risers and bars should make a better all round package and its all just sitting there for free.     just need time to do it....